The Unarchiver - Get the top application for archives on Mac. It's a RAR extractor, it allows you to unzip files, and works with dozens of other formats.
Microsoft BitLocker - BitLocker is a full disk encryption feature included with Windows Vista and later.
Explzh for Windows - Powerful explorer-like archive software for Windows.
Paubox - Paubox provides HIPAA compliant email encryption without the hassle of extra steps.
Engrampa - A file archiver for MATE, based on File Roller from GNOME 2 http://www.mate-desktop.org/
OpenSSH - OpenSSH is a free version of the SSH connectivity tools that technical users rely on.